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Map.prototype.get() - JavaScript | MDN
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Map.prototype.get()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The get() method of Map instances returns the value corresponding to the key in this Map, or undefined if there is none. Object values are returned as the same reference that was originally stored, not as a copy, so mutations to the returned object will be reflected anywhere that reference is held, including inside the Map.
Try it
const map = new Map();
map.set("bar", "foo");
console.log(map.get("bar"));
// Expected output: "foo"
console.log(map.get("baz"));
// Expected output: undefined
Syntax
js
get(key)
Parameters
Return value
The value associated with the specified key in the Map object. If the key can't be found, undefined is returned.
Examples
Using get()
js
const myMap = new Map();
myMap.set("bar", "foo");
console.log(myMap.get("bar")); // Returns "foo"
console.log(myMap.get("baz")); // Returns undefined
Using get() to retrieve a reference to an object
js
const arr = [];
const myMap = new Map();
myMap.set("bar", arr);
myMap.get("bar").push("foo");
console.log(arr); // ["foo"]
console.log(myMap.get("bar")); // ["foo"]
Specifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-map.prototype.get |
Browser compatibility
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